In the modern building construction industry the technique of utilizing panels of standard size in the fabrication of walls, both interior and exterior, roofs, and other building components is now the accepted practice. Today the construction industry uses standard panels for sheet rock, plywood, wood paneling, exterior sheathing, roofing, etc. Standard panel sizes start at about 4'.times.8' and include 4'.times.10' and 4'.times.12' sheets for many applications. One difficulty encountered with sheets of this type is that in certain areas they must be cut out or trimmed to accommodate doors, windows and appliance openings such as electrical outlet boxes, lights and similar items. In addtion, "out of square" conditions in older buildings, particularly must be accommodated. Traditionally, the carpenter has taken multiple measurements of the locations of these cut outs, and marked them off on a panel and cut the panel to fit. This has been time consuming and error prone, although not impossible of accomplishment. An additional problem encountered in the use of paneling has been the location of studs particularly with larger panels.